Manual knife sharpener



FIG. 1 is a perspective view of a manual knife sharpener showing my new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a left end elevational view thereof; and,

FIG. 7 is a right end elevational view thereof.

The broken lines of FIG. 5 illustrate portions of the design that form no part of the claim. 

The ornamental design for a manual knife sharpener, as shown and described. 